What causes the accumulation of protons in the lumen of the thylakoid membrane?

What causes the accumulation of protons in the lumen of the thylakoid membrane?
  1. Transport of electrons through the photosystems
  2. Splitting of water molecules on the inner side of the membrane
  3. Breakdown of the proton gradient
  4. Release of protons from the stroma

Solution

As electrons move through the photosystems, protons are transported across the membrane to the lumen side of the membrane, causing an accumulation of protons in the lumen.

Asked in: NCERT

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